Lee G. Sobotka

Democratic Decay ofBe6Exposed by Correlations

The interaction of an E/A=70-MeV (7)Be beam with a Be target was used to populate levels in (6)Be following neutron knockout reactions. The three-body decay of the ground and first excited states into the α+p+p exit channel were detected in the High Resolution Array. Precise three-body correlations extracted from the experimental data allowed us to obtain insight into the mechanism of the three-body democratic decay. The correlation data are in good agreement with a three-cluster-model calculation and thus validate this theoretical approach over a broad energy range.

Particle decay of {sup 12}Be excited states

The breakup of E/A=50 MeV (12)Be fragments following inelastic scattering off of hydrogen and carbon target nuclei has been studied. The breakup channels alpha+(8)He, (6)He+(6)He, t+(9)Li, and p+(11)Li were observed. Two doublets at excitation energies of 12.8 and 15.5 MeV were found for the alpha+(8)He channel. A low-energy shoulder in the excitation-energy spectra at 10.2 MeV indicates one or more additional states. This work could not confirm the presence of (6)He-(6)He rotational structure reported by Freer [Phys. Rev. C 63, 034301 (2001)], although possible peaks at excitation energies of 13.5 and 14.5 MeV were found for (6)He+(6)He decay. Significant structure is observed in the excitation-energy spectrum for p+(11)Li at 25-30 MeV which maybe associated with T=3 analog states.

Collisions between 48Ti + 93Nb at 917 MeV.

Collisions between {sup 48}Ti + {sup 93}Nb at 19.1 MeV/nucleon were studied using two 4{pi} detection systems. A reconstruction procedure was developed to determine the mass, kinetic, and excitation energies of the primary projectile and targetlike fragments. The results show a broad range of mechanisms. These results were compared with predictions of the quantum-molecular dynamics model. {copyright} {ital 1996 The American Physical Society.}

Energy Dependence of Multifragmentation in 84Kr+197Au Reactions

The relationship between observed intermediate mass fragment and total charged particle multiplicities has been measured for [sup 84]Kr + [sup 197]Au collisions at energies between [ital E]/[ital A]=35 and 400 MeV. Fragment multiplicities are greatest for central or near-central collisions. For these collisions, fragment production increases up to [ital E]/[ital A][approx]100 MeV, and then decreases at higher energies.